Jason's father, Arthur R White, was a porter at Billingsgate Fish Market, and his Welsh-born mother, Olwen Jones, worked as a charwoman. She gave birth to twin boys in Edmonton, Middlesex in February 1940, but Jason's twin brother died during childbirth.[1] It is an urban myth that he chose the name Jason as a tribute to his dead twin:[3] David Jason himself has denied this. In 1984 during an interview on TV-am, David Jason admitted that the name David Jason was taken from his like of Jason and the Argonauts, as the stage name David White had already been taken.

Jason's elder brother is the actor Arthur White, born in 1933. The two appeared together in the crime drama A Touch of Frost, with Arthur playing police archivist Ernie Trigg; and again in 2008, in the comic fantasy, The Colour of Magic, where Arthur starred as a character called "Rerpf". He also appeared briefly with his brother in an episode of The Darling Buds of May. On leaving school, Jason wanted to follow in his brother's footsteps as an actor, but their father insisted that he first get a trade. So, for six years, he trained as an electrician, before giving up his girlfriend at the time, and becoming a jobbing actor.[1]

In the 1970s, he also acted in radio comedies, including the weekly topical satire Week Ending (in which he regularly played such figures as then UK Foreign Secretary Dr David Owen) and The Hitchhiker's Guide to the Galaxy (as the "B Ark Captain" in the sixth episode, in an in-joking reference to his Week Ending role as Owen). Jason also appeared in The Next Programme Follows Almost Immediately and made appearances on panel games such as The Impressionists as well as his own series, The Jason Explanation. In the early 1970s, he appeared in Mostly Monkhouse.

Four series of Open All Hours were made from 1976–85. He featured in Barker's Porridge (BBC), a prison-based comedy, as the elderly Blanco in three episodes. Jason also appeared with Barker in various disguises in The Two Ronnies.

Jason starred in London Weekend Television's Lucky Feller (1975–76), written by Terence Frisby and produced by Humphrey Barclay. About two brothers in South-East London, the series was in many ways a forerunner to Only Fools And Horses, only Jason was in the more dopey 'Rodders' role with Peter Armitage playing the cleverer of the two. The brothers drove around in a comical bubble car, a precursor to the famous Trotters' van; and there was even the gag where, just as he was trying to impress the girl (Cheryl Hall), Jason casually leaned back against the bar, without his knowing that barman had just lifted it behind his back, and fell through. This situation was re-enacted in Only Fools And Horses.[citation needed] He played the lead role in the ATV sitcom A Sharp Intake of Breath (1977–81). In 1979, he appeared as Buttons in the pantomime Cinderella at Newcastle's Theatre Royal, starring Leah Bell and Bobby Thompson, produced by Michael Grayson and directed by John Blackmore.

On 16 September 2008, Jason announced that he would retire his role as Jack Frost after 16 years.[4] Three new episodes of the show were shown in autumn 2008, and were followed by a two-part finale in 2010. Approached by BBC1 controller Danny Cohen in early 2011, he read three scripts and agreed to shoot a pilot for The Royal Bodyguard, which was shown at the Edinburgh Film Festival.[1] The pilot episode aired on the BBC on Boxing Day but received a poor critical response. The series was axed after six episodes.

On the day it was announced, many British newspapers used the headline "Arise Sir Del Boy" or similar, in reference to his most famous role. Upon receiving the knighthood from Queen Elizabeth II at Buckingham Palace on 1 December 2005, he said he was "humbled" by the "fantastic tribute".[6][7]

Jason lived with his long-term girlfriend, Welsh actress Myfanwy Talog, for eighteen years and nursed her through breast cancer until she died in 1995. This experience inspired him to organise his own charity, The David Jason Trust for terminally ill children.[citation needed]

Jason is a patron of the Shark Trust,[9] a United Kingdom registered charity working to advance the worldwide conservation of sharks through science, education, influence and action. He has also been Honorary Vice Patron of the Royal International Air Tattoo since 1999, and on 29 May 2014, presented a cheque on behalf of the Fairford-based RAF Charitable Trust for £125,000 to the British RAF Air Cadet Organisation, to fund flight simulators for Air Cadets.[10]

Jason is a qualified helicopter pilot.[11] In October 2013, Jason released his autobiography called David Jason: My Life.[12] It was shortlisted for the 2013 Specsavers National Book Awards "Best Book of the Year".[13]